(1) Every transfer of an interest in property, other than in trust, made only as a security for the performance of another act is to be deemed a mortgage, except when in the case of personal property it is accompanied by actual change of possession, in which case it is deemed a pledge.
(2) The fact that a transfer was made subject to defeasance on a condition may, for the purpose of showing such transfer to be a mortgage, be proved (except as against a subsequent purchaser or encumbrancer for value and without notice), though the fact does not appear by the terms of the instrument.